/*
* locks.c
*
* Created on: 16.07.2013
* Author: sr
*/
#include "locks.h"
#include "helper.h"
#include "../shared/timing.h"
#ifdef _DEBUG
#define MAXLOCKS (SERVER_MAX_CLIENTS * 2 + SERVER_MAX_ALTS + 200 + SERVER_MAX_IMAGES)
#define MAXTHREADS (SERVER_MAX_CLIENTS + 100)
#define LOCKLEN 60
typedef struct
{
void *lock;
ticks locktime;
char locked;
pthread_t thread;
int lockId;
char name[LOCKLEN];
char where[LOCKLEN];
} debug_lock_t;
typedef struct
{
pthread_t tid;
ticks time;
char name[LOCKLEN];
char where[LOCKLEN];
} debug_thread_t;
int debugThreadCount = 0;
static debug_lock_t locks[MAXLOCKS];
static debug_thread_t threads[MAXTHREADS];
static int init_done = 0;
static pthread_spinlock_t initdestory;
static int lockId = 0;
static pthread_t watchdog = 0;
static dnbd3_signal_t* watchdogSignal = NULL;
static void *debug_thread_watchdog(void *something);
int debug_spin_init(const char *name, const char *file, int line, pthread_spinlock_t *lock, int shared)
{
if ( !init_done ) {
memset( locks, 0, MAXLOCKS * sizeof(debug_lock_t) );
memset( threads, 0, MAXTHREADS * sizeof(debug_thread_t) );
pthread_spin_init( &initdestory, PTHREAD_PROCESS_PRIVATE );
init_done = 1;
}
int first = -1;
pthread_spin_lock( &initdestory );
for (int i = 0; i < MAXLOCKS; ++i) {
if ( locks[i].lock == lock ) {
logadd( LOG_ERROR, "Lock %p (%s) already initialized (%s:%d)\n", (void*)lock, name, file, line );
exit( 4 );
}
if ( first == -1 && locks[i].lock == NULL ) first = i;
}
if ( first == -1 ) {
logadd( LOG_ERROR, "No more free debug locks (%s:%d)\n", file, line );
pthread_spin_unlock( &initdestory );
debug_dump_lock_stats();
exit( 4 );
}
locks[first].lock = (void*)lock;
locks[first].locked = 0;
snprintf( locks[first].name, LOCKLEN, "%s", name );
snprintf( locks[first].where, LOCKLEN, "I %s:%d", file, line );
pthread_spin_unlock( &initdestory );
return pthread_spin_init( lock, shared );
}
int debug_spin_lock(const char *name, const char *file, int line, pthread_spinlock_t *lock)
{
debug_lock_t *l = NULL;
pthread_spin_lock( &initdestory );
for (int i = 0; i < MAXLOCKS; ++i) {
if ( locks[i].lock == lock ) {
l = &locks[i];
break;
}
}
pthread_spin_unlock( &initdestory );
if ( l == NULL ) {
logadd( LOG_ERROR, "Tried to lock uninitialized lock %p (%s) at %s:%d\n", (void*)lock, name, file, line );
debug_dump_lock_stats();
exit( 4 );
}
debug_thread_t *t = NULL;
pthread_spin_lock( &initdestory );
for (int i = 0; i < MAXTHREADS; ++i) {
if ( threads[i].tid != 0 ) continue;
threads[i].tid = pthread_self();
timing_get( &threads[i].time );
snprintf( threads[i].name, LOCKLEN, "%s", name );
snprintf( threads[i].where, LOCKLEN, "%s:%d", file, line );
t = &threads[i];
break;
}
pthread_spin_unlock( &initdestory );
if ( t == NULL ) {
logadd( LOG_ERROR, "Lock sanity check: Too many waiting threads for lock %p (%s) at %s:%d\n", (void*)lock, name, file, line );
exit( 4 );
}
const int retval = pthread_spin_lock( lock );
pthread_spin_lock( &initdestory );
t->tid = 0;
pthread_spin_unlock( &initdestory );
if ( l->locked ) {
logadd( LOG_ERROR, "Lock sanity check: lock %p (%s) already locked at %s:%d\n", (void*)lock, name, file, line );
exit( 4 );
}
l->locked = 1;
timing_get( &l->locktime );
l->thread = pthread_self();
snprintf( l->where, LOCKLEN, "L %s:%d", file, line );
pthread_spin_lock( &initdestory );
l->lockId = ++lockId;
pthread_spin_unlock( &initdestory );
return retval;
}
int debug_spin_trylock(const char *name, const char *file, int line, pthread_spinlock_t *lock)
{
debug_lock_t *l = NULL;
pthread_spin_lock( &initdestory );
for (int i = 0; i < MAXLOCKS; ++i) {
if ( locks[i].lock == lock ) {
l = &locks[i];
break;
}
}
pthread_spin_unlock( &initdestory );
if ( l == NULL ) {
logadd( LOG_ERROR, "Tried to lock uninitialized lock %p (%s) at %s:%d\n", (void*)lock, name, file, line );
debug_dump_lock_stats();
exit( 4 );
}
debug_thread_t *t = NULL;
pthread_spin_lock( &initdestory );
for (int i = 0; i < MAXTHREADS; ++i) {
if ( threads[i].tid != 0 ) continue;
threads[i].tid = pthread_self();
timing_get( &threads[i].time );
snprintf( threads[i].name, LOCKLEN, "%s", name );
snprintf( threads[i].where, LOCKLEN, "%s:%d", file, line );
t = &threads[i];
break;
}
pthread_spin_unlock( &initdestory );
if ( t == NULL ) {
logadd( LOG_ERROR, "Lock sanity check: Too many waiting threads for %p (%s) at %s:%d\n", (void*)lock, name, file, line );
exit( 4 );
}
const int retval = pthread_spin_trylock( lock );
pthread_spin_lock( &initdestory );
t->tid = 0;
pthread_spin_unlock( &initdestory );
if ( retval == 0 ) {
if ( l->locked ) {
logadd( LOG_ERROR, "Lock sanity check: lock %p (%s) already locked at %s:%d\n", (void*)lock, name, file, line );
exit( 4 );
}
l->locked = 1;
timing_get( &l->locktime );
l->thread = pthread_self();
snprintf( l->where, LOCKLEN, "L %s:%d", file, line );
pthread_spin_lock( &initdestory );
l->lockId = ++lockId;
pthread_spin_unlock( &initdestory );
}
return retval;
}
int debug_spin_unlock(const char *name, const char *file, int line, pthread_spinlock_t *lock)
{
debug_lock_t *l = NULL;
pthread_spin_lock( &initdestory );
for (int i = 0; i < MAXLOCKS; ++i) {
if ( locks[i].lock == lock ) {
l = &locks[i];
break;
}
}
pthread_spin_unlock( &initdestory );
if ( l == NULL ) {
logadd( LOG_ERROR, "Tried to unlock uninitialized lock %p (%s) at %s:%d\n", (void*)lock, name, file, line );
exit( 4 );
}
if ( !l->locked ) {
logadd( LOG_ERROR, "Unlock sanity check: lock %p (%s) not locked at %s:%d\n", (void*)lock, name, file, line );
exit( 4 );
}
l->locked = 0;
l->thread = 0;
snprintf( l->where, LOCKLEN, "U %s:%d", file, line );
int retval = pthread_spin_unlock( lock );
return retval;
}
int debug_spin_destroy(const char *name, const char *file, int line, pthread_spinlock_t *lock)
{
pthread_spin_lock( &initdestory );
for (int i = 0; i < MAXLOCKS; ++i) {
if ( locks[i].lock == lock ) {
if ( locks[i].locked ) {
logadd( LOG_ERROR, "Tried to destroy lock %p (%s) at %s:%d when it is still locked\n", (void*)lock, name, file, line );
exit( 4 );
}
locks[i].lock = NULL;
snprintf( locks[i].where, LOCKLEN, "D %s:%d", file, line );
pthread_spin_unlock( &initdestory );
return pthread_spin_destroy( lock );
}
}
logadd( LOG_ERROR, "Tried to destroy non-existent lock %p (%s) at %s:%d\n", (void*)lock, name, file, line );
exit( 4 );
}
void debug_dump_lock_stats()
{
declare_now;
pthread_spin_lock( &initdestory );
printf( "\n **** LOCKS ****\n\n" );
for (int i = 0; i < MAXLOCKS; ++i) {
if ( locks[i].lock == NULL ) continue;
if ( locks[i].locked ) {
printf( "* *** %s ***\n"
"* Where: %s\n"
"* When: %d secs ago\n"
"* Locked: %d\n"
"* Serial: %d\n"
"* Thread: %d\n", locks[i].name, locks[i].where, (int)timing_diff( &locks[i].locktime, &now ), (int)locks[i].locked, locks[i].lockId,
(int)locks[i].thread );
} else {
printf( "* *** %s ***\n"
"* Where: %s\n"
"* Locked: %d\n", locks[i].name, locks[i].where, (int)locks[i].locked );
}
}
printf( "\n **** WAITING THREADS ****\n\n" );
for (int i = 0; i < MAXTHREADS; ++i) {
if ( threads[i].tid == 0 ) continue;
printf( "* *** Thread %d ***\n"
"* Lock: %s\n"
"* Where: %s\n"
"* How long: %d secs\n", (int)threads[i].tid, threads[i].name, threads[i].where, (int)timing_diff( &threads[i].time, &now ) );
}
pthread_spin_unlock( &initdestory );
}
static void *debug_thread_watchdog(void *something UNUSED)
{
setThreadName( "debug-watchdog" );
while ( !_shutdown ) {
if ( init_done ) {
declare_now;
pthread_spin_lock( &initdestory );
for (int i = 0; i < MAXTHREADS; ++i) {
if ( threads[i].tid == 0 ) continue;
const uint32_t diff = timing_diff( &threads[i].time, &now );
if ( diff > 6 && diff < 100000 ) {
printf( "\n\n +++++++++ DEADLOCK ++++++++++++\n\n" );
pthread_spin_unlock( &initdestory );
debug_dump_lock_stats();
exit( 99 );
}
}
pthread_spin_unlock( &initdestory );
}
if ( watchdogSignal == NULL || signal_wait( watchdogSignal, 5000 ) == SIGNAL_ERROR ) sleep( 5 );
}
return NULL ;
}
#endif
void debug_locks_start_watchdog()
{
#ifdef _DEBUG
watchdogSignal = signal_new();
if ( 0 != thread_create( &watchdog, NULL, &debug_thread_watchdog, (void *)NULL ) ) {
logadd( LOG_ERROR, "Could not start debug-lock watchdog." );
return;
}
#endif
}
void debug_locks_stop_watchdog()
{
#ifdef _DEBUG
_shutdown = true;
printf( "Killing debug watchdog...\n" );
pthread_spin_lock( &initdestory );
signal_call( watchdogSignal );
pthread_spin_unlock( &initdestory );
thread_join( watchdog, NULL );
signal_close( watchdogSignal );
#endif
}
